Manufacture of candles and like articles



Jan. 11,1955 D. J. KEOGH 2,698,969

MANUFACTURE OF CANDLES AND LIKE ARTICLES Filed May; 12, 1951 3 Sh eetSSheet l FIG. I

INVENTOR DANIEL JAMES KEOGH Y fifiJ HIS ATTORNEY Jan. 11, 1955 D. J.KEOGH 2,698,969

MANUFACTURE OF CANDLES AND LIKE ARTICLES Filed May 12, 1951 3Sheets-Sheet 2 n g; 8 (5" 'l as M L .4

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C0 o1 INVENTOR DANIEL JAMES KEOGH HIS ATTORNEY Jan. 11, 1955 D. J. KEOGH2,693,969

MANUFACTURE OF CANDLES AND LIKE ARTICLES Filed May 12, 1951 :sShets-Sheet s INVENTOR:

DANIEL JAMES KEOGH HI ATTORNEY United States Patent M MANUFACTURE OFCANDLES AND LIKE ARTICLES Daniel James Keogh, Saltdean, England,assignor to Prices Patent Candle Company Limited, London, England, aBritish company Application May 12, 1951, Serial No. 226,009

Claims priority, application Great Britain May 18, 1950 3 Claims. (Cl.1859) The art of manufacturing candles and like articles has for verymany years proceeded on lines which have not suffered major change.

As regards candles the practice which is probably more Widespread thanany other involves moulding the articles say in batches of 50 or more.In such practice a plurality of water-jacketed moulds through the centreof each of which a wick is disposed, received molten wax and when thishas solidified by cooling, means are provided for sliding the mouldedcandles out of the moulds so as to leave the latter, still containing awick disposed along the centre axis, free to receive a further batch ofmolten material. In the manufacture of tapers or wax wire as used ncertain types of foundry work another practice which is often followedinvolves dipping in a bath of molten wax a long continuous length ofwick disposed on and between two large-diameter rotatable drums. Thewick pulled through the bath by rotation of the large drums picks up oneach successive traverse through the bath a certain amount of wax whichsolidifies wholly or in part on exposure to the atmosphere, and thisbuild-up is allowed to continue until a sufficient deposit of wax issecured.

In both these procedures the wick is impregnated by the molten wax, andindeed such a result has long been deemed essential, or at least highlydesirable, by most workers skilled in this industry.

From time to time proposals have been advanced to make the process offorming candles and like articles continuous. To this end arrangementshave been sug gested to extrude wax, cooled in the extrusion apparatusfrom the liquid to a semi-solid or plastic state, continuously throughorifices around a wick fed continuously to the centres of theseorifices, the wax-covered wick being thereupon subjected to watercooling in order to harden and solidify the wax. In practice however,such proposals have encountered serious difiiculties which haveprevented their commercial adoption. Thus the solidification of theextruded product proceeds in such a manner that a lengthy temperingprocess is needed in order to produce a satisfactory product. Moreover,variations in temperature with consequential variations in plasticity ofthe wax have led to mechanical instability of the extruded product whichhas proved most difficult to handle and process to satisfactory finishedcandles.

The present invention is concerned with a continuous process of makingfinished candles and like articles and is based on considerableexperimental work which has led to the surprising discovery that coldsolid wax can be extruded by pressure through an orifice to give acontinuous rod of wax which, with no cooling of the extruded productother than that occasioned by contact with the atmosphere, is firmenough to handle and process without distortion; and to the furthersurprising discovery that this pressure extrusion of cold solid wax canbe efiected through an orifice which is simultaneously fed with acontinuous length of wick so as to give a continuous rod of wax-coveredwick which is likewise sufiiciently firm to handle and process withoutdistortion to produce finished articles such as candles of a qualitysatisfying commercial requirements. Candles produced by such techniquehave a wick which has not suffered impregnation by the wax because thelatter does not approach the degree of plasticity necessary to secureimpregnation of the wick. Nevertheless the surrounding wax 2,698,969Patented Jan. 11, 1955 adheres firmly to the central wick and thefinished candle or like article burns efficiently under normalconditions of use.

According to the present invention therefore a continuous rod ofwax-covered wick is formed by extruding solid wax through an orificearound a wick which is guided towards the centre of the orifice and isfree to be drawn forward by the extruded wax, the extrusion beingcarried out at a temperature and speed such that, with no cooling of theextruded product other than that occasioned by contact with theatmosphere, the said product is a continuous rod of wax-covered wickwhich is non-brittle and is sufficiently firm to be handled withoutdistortion. If desired, this continuous extruded rod of wax-covered wickis continuously processed to finished candles and like articles bycausing relative movement towards each other of the successive free endsof the rod and a rotating cutter adapted to uncover a short length ofwick at the said end of the rod, and then cutting off in succession thedesired lengths of rod to form candles.

A preferred form of the invention is illustrated by way of example bythe accompanying drawings, which show a machine for extruding a rod ofwax-covered wick according to the invention and converting this rod intocandles by successively uncovering a short length of wick at the forwardend of the rod to form a tip, and then cutting off the desired length ofrod. In the drawings,

Figure 1 is a perspective view of the extruding apparatus,

Figures 2A and 2B are sectional and exploded perspective viewsrespectively of the extrusion nozzle,

Figure 3 is a side elevation of the tipping and cutting apparatus, and

Figure 4 is an end view of the apparatus shown'in Figure 3, taken on theline IVIV of that figure.

The extruding apparatus shown in Figure 1 is mounted in a frameworkcomprising girders 1, 2, 3 and 4, standards 5, 6 and 7, plates 8, 9 and10 bolted together by bolts such as 11 and 12. and a cross beam 19. Theextrusion is effected by hydraulic pressure, a supply of hydraulic oilbeing contained in a tank 13 and subjected to pressure by a pump 14driven by a motor 15. The hydraulic cylinder 16 is mounted between theplates 8 and 9, and the extrusion cylinder 20 is held by the plate 8 anda strap 17 welded to the beam 19. Contained in cylinder 16 is thehydraulic piston whose piston rod passes through a gland in plate 9 andcarries on its exposed end the extrusion ram 18. The hydraulic piston isoperated by a conventional hydraulic system comprising the tank 13, pump14 and valve 22.

The extrusion nozzle shown in section in Figures 2A and 2B comprises abase plate 28 bolted to the plate 7, a nozzle plate 29 hinged to thebase plate 28 at 30, and a die plate 31 bolted to the nozzle plate 29and having an extrusion orifice 32. The nozzle assembly can be clampedin position for extrusion, as shown in Figure 2A, by means of a lever 33pivoted to the base plate 28, the plate 29 being centered by means of aboss 37 on the plate 28 which has a conical surface co-operating with alike surface in the plate 29. The rear face of the plate 29 is providedwith a slot 39 in which is fixed by means of screws not shown in thedrawing the rectangular shank 34 of a wick tube. The tip of the wicktube is bent at 35 so that a wick threaded through the tube issues onthe axis of the orifice 32. A length of wick is carried on a spool 36(Figure l) which is mounted on the plate 8 so as to be capable of freerotation. When the nozzle plate assembly is brought into the extrusionposition, the shank 34 of the wick tube is accommodated by a slot 38 inthe boss 37. A stripper cone 42 is secured to plates 40a and 40b whichare themselves fixed to the die plate 31 by bolts 43, a clearancebetween the plate 40a and die plate 31 being maintained by washers 41.The rear or smaller edge of the cone 42 is sharpened for the purpose ofstripping the extruded wax rod, as described below.

In order to charge the machine with wax, the nozzle plate assembly isreleased by operation of the lever 33 and a rod of solid wax is pushedinto the extrusion cylinder 20 through the hole 44 in the base plate 28,this hole being of the same diameter as the extrusion cylinder. The waxrod may be produced by casting and is as nearly as possible equal indiameter to the extrusion cylinder, so that the rod makes a sliding orpush fit in the cylinder. When the wax rod has been inserted, the nozzleplate assembly, after ensuring that a length of wick protrudes throughthe orifice 32, is closed and clamped in position by the lever 33. Thevalve 22 is then operated to supply the rear of the cylinder 16 with thepressure fluid, so that the ram 18 begins to extrude the wax through theorifice 32. The extruded rod is formed round the wick protruding fromthe wick tube, the wick being drawn forward by the wax as the latteradvances through the extrusion nozzle.

The temperature of the wax, which was inserted into the machine at roomtemperature, is raised by the extrusion process to an extent dependingon the speed of extrusion. This speed must not be sufiiciently great toheat the wax to a temperature such that cooling (other than any coolingwhich is necessarily occasioned by contact of the rod with theatmosphere) is necessary in order to render the rod firm enough to behandled without distortion. This maximum permissible speed dependspartly on the composition of the wax and partly on the ambienttemperature. If desired, in hot climates, the extrusion cylinder and/ ornozzle assembly may be provided with water cooling in order to increasethe speed at which the extrusion can be carried out. By governing theextrusion process in such a manner that cooling of the extruded productis unnecessary, not only is the necessity of providing extensive coolingbaths avoided, but a superior product which is less liable to distortionor breakage is obtained.

As an example of a speed which has been found satisfactory for producingsmall candles such as are used for decorating cakes, it proved to bepossible to produce 300 such candles a minute at a room temperature ofabout 65 to 70 F., without any artificial cooling. In this instance awax of the following composition: parafiin wax of melting point l35140F., 89.5 per cent., stcarin 7.5 per cent, beeswax 3 per cent, wasextruded under a pressure of the order of 2000 pounds per square inch ina hydraulic cylinder of 6 inch diameter from an extrusion cylinder of1%; inch diameter through an orifice of inch diameter. The extruded rodwas cut into candles, as described below, each having a length of about2 inches.

In order to ensure that there is no inclusion of air pockets in the Wax,the rod of wax is, as stated above,

made to fit closely in the extrusion cylinder. Inclusion of air wouldlead to the formation of blow holes or, in extreme cases, todisintegration of the product. It is further desirable that thedifference in pressure between the wax in the interior of the extrusioncylinder and as it leaves the extrusion orifice shall not be too great,since too great a pressure difierential in some cases reduces the cherence or tenacity of the product.

Whi e the extrusion orifice 32 is shown as being circular in shape,orifices of other shapes may be used, denendinq on the section requiredfor the extruded rod. Like ise the orifice may be provided with ahelical groove for r d cing decorative candles having a helicalexterior.

On emerging from the extrusion orifice 32, the rod n ss s through thehole formed by the small edge of the stripper c ne 42. This hole is ofslightly less diameter th n the orifice 32 and serves to strip a thinouter layer from the extruded rod. the wax thus removed escaping throuwhthe clearance between plate 4% and die plate 31. The ob ect of thisstrioning process is to remove any s i ht surface irregularities whichmay have been caused by the extrusion, so that the rod after strippinghas a smooth polished surface which is not inferior to that which can beobtained by moulding the wax. If the rod is to be used for a purpose forwhich surface finish is of no importance. for example, as wax wire, thestrioner cone may be omitted.

After passing throu h the stripper cone, the rod is led to the tippingand cutting machine shown in Figures 3 and 4, for conversion intocandles. In order to permit the tinning and cutting machine to workcontinuously in spite of interruptions in the operation of the extrusionmachine to enable a fresh rod of wax to be inserted in the extrusioncylinder, the extruded rod may, where its diameter is sufficiently smallto make the procedure practicable, be passed through a loop-formingdevice as shown in Figure l. The device shown comprises a pulley 50mounted in a frame 51 which is capable of running on inclined rails 52.The extruded rod 53, after issuing from the stripper cone 42, passesover the pulley 50 and then over a pulley 54 rotatably mounted on anaxle fixed in a frame 55 which also supports the rails 52 at one endthereof. When the extruding machine is working, it extrudes the rod at aslightly greater rate than the average rate at which the latter is fedto the tipping and cutting machine. The loop formed round the pulley 5)thus increases in length, the frame 51 taking up the slack by runningdown the rails 52. When the extrusion machine is stopped for recharging,the loop of wax rod shortens and the pulley 50 runs up the rails 52.Thus the supply of rod to the tipping and cutting machine remainssteady. The device shown is suitable, for example, for use with wax rodwhich is to be made into small candles such as are used for decoratingcakes.

The machine shown in Figures 3 and 4 comprises a set of four pairs offeed rollers 69 which grip the rod 53 and advance it intermittentlytowards a tipping cutter head 61 which is fixed on the shaft of sn allelectric motor 62 and continuously rotated thereby. When the rollers,which are driven by a mechanism indicated generally at 63, have advancedthe rod through nearly the length of one candle, the motor 62 and tippmgcutter head 61 are moved to the left (as seen in Figure 3) by a cam 64and arm 65 so as to meet the advanc' g rod 53 and cut a conical tip onthe rod, leaving a short I t wick exposed for lighting the candle. Aftercu conical tip, the tipping cutter head 61 is moved a the right. As thetipping operation is cor rollers 69 hold the rod 53 stationary and a kblade 66 carried by a rotor 67 parts the rod so as to produce a finishedcandle. As each candle is parted an arm 68 pushes it transversely into achute 69.

it may be convenient to arrange several extrusion cylinders on a singlebed and actuate the several ran .cm a common source of hydraulic fluid.Alternan sly a. single extrusion cylinder may be provided with a on 1 ofdie plates and extrusion orifices. Thus, for er the feed rollers 60,tipping cutter head 61 and shown in Figures 3 and 4 may conveniently bed'. and this duplicate machine could be fed by truded by the samehydraulic apparatus or c cylinder.

The apparatus suitable for carrying out this method is further describedand claimed in copending application Serial No. 226,010. filed May 12,ll, now Patent No. 2,657,425.

I claim:

1. A method of making a continuous rod of waxcovered wick for themanufacture of wax candles, tapers, wax wire and the like whichcomprises introducing a coherent mass of solid wax into an extrusioncylinder, extruding a continuous rod of wax-covered wick by forcingsolid wax consisting predominantly of parar'fin wax from the extrusioncylinder into a wick-receiving chamber, said wick being guided towardthe center of said chamber and supplied freely to said chamber, wherebysaid wick is drawn forward by the wax, forcing the wax-covered wickthrough an extrusion orifice of substantially smaller crosssectionalarea than that of the wick receiving chamber, and continuously passingthe extruded rod through a stripper orifice having an orifice similar tobut of slightly smaller size than the extrusion orifice, andcontinuously stripping off and removing from the surface of the rod andfrom the entry edge of the orifice in solid form any wax surfaceirregularities which may have been formed thereon by the extrusion, saidprocess being carried out without externally applied change intemperature of the wax other than that occasioned by contact with theatmosphere, and at a temperature and at a speed such that the extruded,continuous rod is non-brittle and sufificiently firm to be handledwithout distortion.

2. A method of making tipped waxed candles, tapers and the like whichcomprises introducing a coherent mass of solid wax into an extrusioncylinder. extruding a continuous rod of wax-covered wick by forcingsolid wax consisting predominantly of paraffin wax from the extrusioncylinder through an extrusion orifice around a continuous length ofwick, said wick being guided toward the center of the orifice andsupplied freely to said orifice, whereby said wick is drawn forward bythe extruded wax,

i the to the i said extrusion being carried out without cooling of theextruded product other than by contact with the atmosphere and at atemperat re and at a speed such that the extruded, continuous rod isnon-brittle and sufliciently firm to be handled without distortion,advancing the extruded rod of Wax-covered wick to a variable lengthtakeup device at a rate determined by the said speed of the extrusion,withdrawing the rod from said device at a periodically variable rate,and successively tipping the outer end of the rod by cutting waxperipherally to uncover a short length of the wick at said end, andcutting off a length of the tipped rod to form a candle, saidperiodically variable rate of withdrawal being determined by andsynchronized with said tipping and cutting operations independently ofsaid extrusion.

3. A method of making tipped waxed candles, tapers and the like whichcomprises introducing a coherent mass of solid wax into an extrusioncylinder, extruding a continuous rod of a wax-covered wick by forcingsolid wax consisting predominantly of paraffin wax from the extrusioncylinder through an extrusion orifice around a continuous length ofwick, said wick being guided toward the center of the orifice andsupplied freely to said orifice, whereby said wick is drawn forward bythe extruded wax, said extrusion being carried out without cooling ofthe extruded product other than by contact with the atmosphere and at atemperature and at a speed such that the extruded, continuous rod isnon-brittle and suificiently firm to be handled without distortion,continuously passing the extruded rod of wax-covered wick through astripper orifice having an orifice similar to, but of slightly smallersize than the extrusion orifice, and stripping off from the surface ofthe rod in solid form any surface irregularities which may have beenformed thereon by the extrusion, advancing the extruded rod ofwax-covered Wick to a variable length takeup device at a rate determinedby the said speed of the extrusion, withdrawing the rod from said deviceat a periodically variable rate, and successively tipping the outer endof the rod by cutting wax peripherally to uncover a short length of thewick at said end, and cutting off a length of the tipped rod to form acandle, said periodically variable rate of withdrawal being determinedby and synchronized with said tipping and cutting operationsindependently of said extrusion.

References Cited in the file of this patent UNITED STATES PATENTS 4,389Drummond Feb. 20, 1846 1,294,008 Will Feb. 11, 1919 1,482,000 EngmanIan. 29, 1924 1,483,555 Sevigne Feb. 12, 1924 1,571,589 Kerr Feb. 2,1926 FOREIGN PATENTS 360,995 Great Britain Nov. 19, 1931

